Category Archives: Pest Group

Corn earworm report–August 13, 2020

Posted on August 13, 2020 by Sean Malone

Average nightly corn earworm/bollworm moth black light trap captures for this week were: Dinwiddie = 26; Greensville =4; Prince George-Templeton = 9; Prince George-Disputanta = 6; Southampton = 8; Suffolk = 23. Thanks to our Agents and Growers for their efforts. Here is the data table

Sally Taylor and her entomology program sampled a Cotton Incorporated sponsored planting date experiment today at the Tidewater AREC in Suffolk, VA. We found 2 to 6.5% bollworm-injured bolls in conventional (non-genetically protected against bollworm) cotton. In our Virginia Soybean Board experiment with maturity groups 4 and 5 full-season soybean (beginning pod growth stage), we had 2.3 to 5 corn earworm larvae and up to 3 soybean looper larvae per 15 sweeps.

Corn earworm update for August 6, 2020

Posted on August 6, 2020 by Sean Malone

Average nightly moth captures for this week were: Greensville =10; Prince George-Templeton = 3; Prince George-Disputanta = 7; Suffolk = 21. Here is the data table

Corn earworm update for July 30, 2020

Posted on July 30, 2020 by Sean Malone

Black light trap nightly averages for corn earworm/bollworm moths this week in Virginia were: Greensville = 35.6; Prince George-Templeton = 1.0; Prince George-Disputanta = 3.3; Southampton = 2.0; Suffolk = 17.1 (all reports were higher than last week). Thanks to our Agents for their reports.

Resistance monitoring of corn earworm/bollworm using adult vial tests now has 50% of moths surviving the 24-hour exposure to the pyrethroid, cypermethrin at the 5 microgram/vial rate (76 vials tested to date, collected from Suffolk).

Corn earworm moth report for July 23, 2020

Posted on July 23, 2020 by Sean Malone

Prior to this week, corn earworm/bollworm moth counts have been low in southeast Virginia black light traps. For this week (July 17-23), average nightly catches of moths were: Greensville = 7.4; Prince George-Templeton = 0.3; Prince George-Disputanta = 0.7; Southampton = 1.5; Suffolk = 7.4. Thanks to the Virginia Cooperative Extension Agents who are operating traps this season.

We have tested 47 corn earworm/bollworm moths since June 23, 2020 in our pyrethroid resistance monitoring program. Moths are captured in pheromone traps and are exposed to 5 micrograms of cypermethrin inside a glass vial for 24 hours, then rated as dead/down/alive. Untreated controls (in acetone-only treated vials) are also evaluated to correct for control mortality. The average for the past month is 43% moth survival. High survival rates indicate an increased chance of pyrethroid control issues and the need to consider alternative chemistries if a spray is needed.

In a non-Bt corn experiment planted on April 9 at our research farm in Suffolk, VA, we had large corn earworm larvae in the ears last week. Now they have exited the ears and are pupating in the soil. It takes about 10 days for the moths to emerge–this flight out of corn is the one that we are concerned with in crops such as soybean, cotton, peanuts, and vegetables–the moths want to lay eggs on a good food source for their larvae. Please check back with the Advisory for more pest updates and recommendations.

Herbicide Resistant Weeds Workshops

Posted on March 4, 2020 by Michael Flessner

CANCELLED! Due to Virginia Tech’s response to COVID-19 and out of concern for everyone, we are cancelling all of these workshops. We will reschedule after field season in Nov. or Dec.

Topics:

Common ragweed infesting a soybean field.

Herbicide Resistance- What is it and how did we get here?
Creating Effective Herbicide Plans
Integrated Weed Management of Palmer amaranth, common ragweed, and horseweed/marestail
Local Perspective on Weed Management
Putting It All Together: Creating a Weed Management Plan

CCA credits will be offered

Free lunch to start or end the program!

If you are a person with a disability and desire any assistive devices, services or other accommodations to participate in this activity, please contact the Extension office listed above or TDD* during business hours of 8:00 a.m. and 5:00 p.m. to discuss accommodations 5 days prior to the event. *TDD number is (800) 828-1120.

Virginia Cooperative Extension programs and employment are open to all, regardless of age, color, disability, gender, gender identity, gender expression, national origin, political affiliation, race, religion, sexual orientation, genetic information, veteran status, or any other basis protected by law. An equal opportunity/affirmative action employer.

Northern Neck Crops Conference – Warsaw, VA

Posted on January 9, 2020 by David Holshouser

The 2020 Northern Neck Crops Conference will be held Thursday, Jan. 16 at the Cobham Park Baptist Church, 13829 History Land Hwy Route 3, Warsaw, VA 22572. This year’s conference will include pesticide certification training, updates from FSA, NRCS, and SWCD, and several Specialists and Agents from Virginia Cooperative Extension that will cover a wide variety of topics. We look forward to seeing your there for a great day of learning and interaction with the experts. Lunch will be provided. Agenda detail are below.

Full Attendance to the conference has been approved for Private Pesticide Applicator Recertification in Category 90 & 91, and Commercial Categories 1A, 10, and 60. The conference has also been approved for 1.0 Virginia Nutrient Management CEU and 4.0 CCA-CEU credits.

9:00 – 9:05 Welcome – Trent Jones, VCE – Northumberland & Lancaster

9:05 – 9:50 Using Cover Crops for Weed Control – Michael Flessner, VCE – Weed Science Specialist

9:50 – 10:35 Market Update Robert Harper, Virginia Farm Bureau -Grain Division Manager

10:35 – 10:40 Irrigation Resources – Julie Shortridge, VCE – Biological Systems Engineering Specialist

10:40 – 10:55 BREAK – Please visit with our sponsors!

10:55 -11:40 IPM Updates – Sally Taylor, VCE – Entomology Specialist

11:40 – 12:35 Weathering the Storm: How to Cultivate a Productive Mindset – Jeremy Daubert, VCE – Rockbridge County

12:35 – 1:15 LUNCH

1:15 – 1:20 Program Updates – Scott Hammond, NRCS – Soil Conservationist

1:20 – 1:25 Program Updates – Brandon Dillistin, NNSWCD – District Technical Manager

1:25 – 2:15 Corn and Small Grain Production Update – Wade Thomason, VCE – Grains Specialist

2:15 – 2:30 Break & Evaluations

2:30 – 3:00 Legal Updates – Robert Christian, Pesticide Investigator – VDACS

3:00 – 3:30 Safety Updates – Trent Jones & Stephanie Romelczyk, VCE – Northern Neck

3:30 – 3:40 Wrap Up & Paperwork

2020 Five County Agricultural Conference – King William, VA

Posted on January 9, 2020 by David Holshouser

The 2020 Five County Agricultural Conference will be held Wednesday, Jan. 15 at the King William Ruritan Club Building, 156 Ruritan Lane, King William, Virginia 23086. This year’s conference will include pesticide certification training, updates from FSA, NRCS, and SWCD, several Specialists and Agents from Virginia Cooperative Extension that will cover a wide variety of topics, and precision agriculture round-table discussion. In addition, you will be able to get your dicamba herbicide certification with training being offered by Don Cline of BASF. We look forward to seeing your there for a great day of learning and interaction with the experts. Lunch will be provided. Agenda detail are below.

Full Attendance to the conference has been approved for Private Pesticide Applicator Recertification in Category 90 and Commercial Categories 1A, 10, and 60. The conference has also been approved for 1.5 Virginia Nutrient Management CEU, 2.5 Integrated Pest Management and 1.5 Crop Management CCA-CEU credits.

7:45 a.m. Registration

8:15 a.m. Grain Market Update, Robert Harper, Manager, Virginia Farm Bureau Grain Division

8:45 a.m. Corn Update and Hybrid Selection – Dr. Wade Thomason

9:15 a.m. Break

9:30 am. Soybean basics and Soybean Variety Selection- Dr. David Holshouser, Extension Soybean Agronomist

10:00 a.m. Crop Fertility and Fertilizers – Dr. Hunter Frame

10:30 a.m. Precision Ag Discussion

11:45 a.m. Cooperating Agencies (FSA, NRCS, and SWCD)

12:30 p.m. Sponsored Lunch (Participants not seeking pesticide applicator recertification or Dicamba Certification are welcome

to adjourn following lunch)

1:15 p.m. Dicamba Certification – Don Cline, BASF Crop Protection

1:45 p.m. Legal Update – Robert Christian, VDACS Pesticide Investigator

2:15 p.m. Spill Response Activity – Robbie Longest/Mike Broaddus, Extension Agents, ANR, Essex and Caroline

3:00 p.m. Wrap up paperwork and adjourn

2020 Four Rivers Agricultural Conference – Providence Forge, VA

Posted on January 9, 2020 by David Holshouser

The 2020 Four Rivers Agricultural Conference will be held Tuesday, Jan. 14 at Providence Forge Recreation Center: 9900 Carriage Rd, Providence Forge, 23140. This year’s conference will include pesticide certification training, several Specialists and Agents from Virginia Cooperative Extension that will cover a wide variety of topics, and others. In addition, you will be able to get your dicamba herbicide certification with training being offered by Don Cline of BASF. We look forward to seeing your there for a great day of learning and interaction with the experts. Lunch will be provided. Agenda detail are below.

Full Attendance to the conference has been approved for Private Pesticide Applicator Recertification in Category 90 and Commercial Categories 1A, 10, and 60. The conference has also been approved for 2.5 Virginia Nutrient Management CEU and 2.0 Contact hours for DCR Conservation Planner Re-Certification

9:00 Registration Opens/Meet with Vendors

9:30 Welcome

9:35 Controlling your Drops highlighting dicamba and glyphosate– Laura Maxey-Nay, Hanover Ag Agent

10:00 Pesticide Training – droplet size/playdough- Ed Olsen, Henrico Ag Agent

10:30 Pesticide Legal Update – Robert Christian, VDACS

11:00 2nd round of registration for those not needing pesticide recertification credit

11:15 Dicamba Certification – Don Cline, BASF

12:15 Sponsored Lunch/Meet with Vendors

1:00 Agency updates

1:15 Grain Market Update- Robert Harper, Manager, Virginia Farm Bureau Grain Division

1:45 What I learned from Argentina Agriculture, pest control and nutrient management –Paul Davis

2:05 Corn Update and Hybrid Selection, Dr. Wade Thomason, Extension Grain Agronomist

2:35 Break (visit with sponsors)

2:50 Positioning Your Full-Season Soybean for Maximum Yields, Dr. David Holshouser, Extension Soybean Agronomist

3:20 Making insect management decisions now by purchasing seed for next season, Sally Taylor, Extension Grain Entomologist

3:50 Nematode Panel, various specialists will discuss current nematode control practices.

4:50 Adjourn and paperwork

Tri-County Crop Production Conference – Carson, VA

Posted on January 9, 2020 by David Holshouser

The 2020 Tri-County Crop Production Conference will be held Tuesday, Jan. 14 at the Carson Volunteer Fire Department on 19806 Halifax Rd in Carson, VA. This year’s conference will host several Specialists from Virginia Tech that will cover a wide variety of topics. In addition, you will be able to get your dicamba herbicide certification with training being offered by Don Cline of BASF. We look forward to seeing your there for a great day of learning and interaction with the experts. Lunch will be provided. Agenda detail are below.

9:00 – 9:05 Welcome and Announcements

9:05 – 9:40 Positioning Your Full-Season Soybean for Maximum Yields– Dr. David Holshouser

There are many things we can do to increase full-season soybean yield, but decisions made before planting are the most important. This presentation will focus on site-specifically positioning your crop to best take advantage of the limiting resources of water, light, and nutrients.

9:40-10:20 Plant disease management – Dr. David Langston

Nematode and disease interaction issues in soybeans. Update on fungicide and seed treatments available for corn and soybeans. Common diseases occurring in 2019.

10:20-10:40 Break

10:40 – 11:10 Update on insect pest management – Dr. Sally Taylor

Review of major insect pests in 2019. Recommendations for preparing for 2020, scouting tips to use throughout the season, and updates on insecticides available for use.

11:10 – 11:40 Small Grain and Corn Update – Dr. Wade Thomason

Review of the latest research in corn and small grain production in Virginia.

11:40 – 12:00 Getting Started with Irrigation and Irrigation Survey – Dr. Julie Shortridge

Irrigation is not used on a wide scale in Virginia. This presentation will introduce our new water specialist and a irrigation survey for growers.

12:00 -12:45 Lunch

12:45 – 1:15 Pesticides in VA update – Robert Christian, VDACS

Update on federal record keeping and worker protection standard. Additional information on changes in pesticide labeling for VA. PPE review for commonly used pesticides. Changes to paraquat labeling, handling, and training.

1:15 – 1:35 Weed control update – Scott Reiter

Roundup resistant common ragweed is common in our soybean cropping systems. There are also 4 different herbicide technology systems in play for the 2020 season. We will cover the options available and the stewardship needed to keep the herbicides on the target crops.

1:35 – 1:55 Cover crops – Mike Parrish

Cover crops have many uses in our production systems. Soil erosion control, soil health properties, weed control, and moisture retention. Presentation will cover results from local cover crop plots and impact on these properties.

1:55 – 3:00 On Target Academy – Don Cline, BASF

This session will cover the required training for using dicamba herbicide in post-emerge applications to Xtend soybeans and cotton. Applicator & recordkeeping requirements, nozzle selection and technology, buffer requirements, weather conditions, and tank mix additives will be explained in detail

Full Attendance to the conference has been approved for Private Pesticide Applicator Recertification in Commercial Categories 1A, 10, and 60.

Corn earworm pest problems on hemp and results of recent insecticide tests

Posted on September 23, 2019 by Thomas Kuhar

By: Tom Kuhar (Entomology Professor, Virginia Tech), Kadie Britt (Ph.D. student researching hemp IPM), and Helene Doughty (Entomologist, Eastern Shore AREC, Painter, VA)

Fig. 1. Corn earworm damaging CBD hemp in Virginia. Photo by Kadie Britt.

Corn earworm has become one of the most important pests of hemp, Cannabis sativa, in Virginia and many other states (Fig. 1). Please see our factsheet on this insect as it relates to hemp: https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/ENTO/ento-328/ENTO-328.pdf

Corn earworm can be quite damaging to the seed heads of hemp grown for grain (Fig. 2), but, as we’ve seen recently in Virginia, the pest can also damage hemp grown for CBD oil. Over the past few weeks, corn earworm densities and damage to CBD hemp has reached very high levels throughout Virginia, and their presence in fields has been associated with increased flower bud rot (Fig. 3). This can result in significant economic damage to that crop.

Due to strict regulations on pesticide use on hemp, insecticide recommendations for managing this pest are quite limited at this time. Recently, we evaluated the efficacy of some naturally-derived pesticides that can be legally applied on hemp in Virginia and one naturally-derived (OMRI-certified) insecticide that currently is not allowed to be applied on hemp (Spinosad).

Fig. 1. Corn earworm damage to grain hemp. Photo by Helene Doughty, Eastern Shore AREC.

Fig. 2. Bud rot on CBD hemp. Photo by Kadie Britt.

Eastern Shore Insecticide Field Trial:

Treatments included:

Gemstar (5 fl oz/A) – which is a nuclear polyhedrosis virus that is specific to the corn earworm species. The virus causes corn earworm to become sick and die. Fig. 4. Shows a corn earworm killed by the virus.
Javelin WG (8 oz/A) – Bacillus thuringiensis (Bt) strain kurstaki – bacterial crystalline proteins that kill caterpillars.
Dipel DF (16 oz/A) – Bt kurstaki different formulation
BoteGHA (32 fl oz/A) – Beauveria bassiana – entomopathogenic fungi
Entrust (5 oz/A) – Spinosad derived from soil microbes. *cannot legally be applied on hemp in Virginia.

Fig. 4. Corn earworm killed by virus (Gemstar insecticide). ESAREC 2019. Photo by Helene Doughty.

We evaluated their efficacy in the field on the Eastern Shore of Virginia in a randomized complete block small plot trial. Hemp plots were sprayed twice (1 week apart) and numbers of live CEW larvae and damage was assessed. Results are shown in Figs. 5 & 6. Entrust was the only product that provided effective control of CEW. Unfortunately, this is the one product that we evaluated that is not allowed to be applied on hemp. The insecticide Entrust is OMRI-certified however.

Fig. 5. Numbers of live corn earworm larvae on hemp plants after insecticide treatments at the ESAREC, Painter, VA.

Fig. 6 Corn earworm damage to hemp seeds in the field after insecticide treatments.

Virginia Tech bioassay trial:

Treatments included:

Gemstar (5 fl oz/A) – which is a nuclear polyhedrosis virus that is specific to the corn earworm species. The virus causes corn earworm to become sick and die. Fig. 3. Shows a corn earworm killed by the virus.
Javelin WG (8 oz/A) – Bacillus thuringiensis (Bt) strain kurstaki – bacterial crystalline proteins that kill caterpillars.
Dipel DF (16 oz/A) – Bt kurstaki different formulation
Xentari (16 oz/A) – Bacillus thuringiensis , subsp. aizawai , Strain ABTS-1857
BoteGHA (32 fl oz/A) – Beauveria bassiana – entomopathogenic fungi
Entrust (5 oz/A) – Spinosad derived from soil microbes. *cannot legally be applied on hemp in Virginia.

In order to evaluate the efficacy, untreated hemp seed heads were collected from Kentland Farm and dipped in each of the treatments. Approximately 1 oz of seeds was placed per diet cup and four reps of 10 cups each were set up for the aforementioned six insecticide treatments. CEW larvae (3^rd instar (medium sized) were collected from sweet corn planted at Kentland Farm and were immediately placed 1 larva per cup. Mortality was evaluated 1, 2, 3, and 4 days after treatment (Fig. 7). Similar to the Eastern shore field trial, Entrust provided the most effective control of CEW. However, this trial also included the Bt aizawai product Xentari, which also provided significant control (better than the other products except spinosad. Xentari is allowed for use on hemp in Virginia. For best management of corn earworm during this time, apply Bt products on hemp every few (2-3) days in early morning or late evening. Corn earworm must consume the insecticide for the application to be effective, so ensure good spray coverage on plants. Dead worms may not be noticed until 48 hours after first application.